This invention relates to a catalytic component for polymerization of olefins and a catalytic system containing the same.
Various types of Ziegler-Natta catalyst are known as a catalyst for polymerization of olefins. By the use of these catalysts olefin polymers of stereospecificity are obtained, However, the yield of polymer per unit weight of the titanium catalytic component, i.e. the polymerization activity is still low and also, it is necessary to remove catalytic residues from the polymers thus obtained. For the purpose of eliminating these disadvantages there are provided a process of copulverizing titanium halide and a magnesium halide-electron donor compound adduct and a process of copulverizing magnesium halide and an electron donor compound and contacting the copulverized product with titanium halide (Japanese Patent Publication No. 52-39431 and Japanese Patent Kokai No. 52-151691). However, these processes are not yet satisfactory increasing in the polymerization activity and stereospecificity so that a considerable amount of amorphous polymers and catalytic residues is present in the olefin polymers obtained.
Also, it is known to use a product obtained by adding an electron donor compound and titanium halide to magnesium halide without mechanically pulverizing as a catalyst for olefin polymerization. This catalyst, however, has a low polymerization activity and is not intended for practical use.